1. Field of the Invention
The present invention broadly relates to methods for manufacturing printing devices. Particularly, the present invention relates to a method for inserting to an ink container an absorbent to be impregnated with liquid ink, larger than the receiving space of the ink container, and relates to a container receiving the absorbent inserted by the method.
2. Description of the Related Art
Hitherto, a printing device for a miniaturized ink-jet printing apparatus has been proposed, in which an integral type device including a printing head and an ink container is detachably installed. Such integral cartridge-type device must apply a predetermined level of reduced pressure in the printing head with respect to the pressure in the ink container. A method for obtaining a proper ink flow from the ink container to the printing head under such a reduced pressure is known, in which the ink container receives an absorbent impregnated with ink.
In the process of manufacturing the above-described ink container, the absorbent in a compressed state is manually inserted to the ink container and impregnated with ink. Such manual operation is time consuming and inadequate for the production in volume. Also, a problem is found that the absorbent gets improperly wrinkled when inserted, and/or unevenly contacts to the inner wall of the ink container.
The ink stays gathered in the wrinkles of the absorbent and/or in the gaps between the absorbent and the inner wall of the ink container, which are formed by the above-described manual operation. The ink stagnant in the wrinkles and/or the gaps remains unused, preventing smooth ink supply flow and proper ink jetting for printing, thus deteriorating printing quality.
A method is known in which, in order to overcome the above-described problem, the absorbent is evenly compressed by a jig before insertion to the ink container. The absorbent inserted to the ink container in an evenly compressed state provides no room for ink to stay gathered. Even that, however, the ink added to the absorbent can not be efficiently used out.
In order to efficiently utilize the ink in the ink container, the density of the absorbent is preferably increased gradually toward the ink outlet for the printing head.
A method for producing a density distribution in an absorbent received in a container is proposed, in which the absorbent is inserted to the container through an opening, in a manner that two pairs of the opposed sides of the absorbent are evenly pressed by a pair of first pressing members and a pair of second pressing members respectively, and the container is moved to receive the absorbent while one of the remainder sides of the absorbent free from the first and second pairs of pressing members is pushed by a third pressing member. The first and the second pressing members are removed in accordance with the timing of the third pressing member moving in. Another method is known, for controlling density distribution of the absorbent by controlling moving speed of the container and friction coefficient between the absorbent and the pressing members.
In the above methods, however, the density distribution state in the absorbent is hardly stabilized because the friction coefficient between the pressing members and the absorbent varies according to the amount of the triboelectric charges produced by the friction between the absorbent and the pressing members and between the pressing members and the container and stored on the pressing members, in the course of repeated operation of the absorbent insertion.
The conventional methods, moreover, do not sufficiently enable a desired density distribution in the absorbent to be obtained, because the density distribution is intended to be produced by controlling only timing of in-out movements of the pressing members.
Accordingly, it is an object of the present invention to provide a method for inserting an absorbent, and a container receiving an absorbent inserted thereby, in which, by removing the electric charges stored on pressing members, friction coefficient fluctuation caused in the course of repeated insertion is suppressed to stabilize received state of the absorbent in the container, the removal of charges also serving to suppress the risk of receiving dust in the container, by reducing the dust amount to be adsorbed on the pressing members in the absorbent insertion process.
It is another object of the present invention to provide a method for inserting an absorbent to a container, as well as a container receiving the absorbent, wherein the absorbent is arranged before insertion to the container so that the absorbent has a desired density distribution.
It is a further object of the present invention to provide a method for inserting an absorbent to a container, enabling a desired density distribution in the absorbent to be maintained after repeated insertion process of the absorbent arranged to have the desired density distribution.
In an aspect of the present invention, a method for inserting an absorbent to a container of which receiving space is smaller than the absorbent, comprises the steps of compressing the absorbent with a pressing member, inserting the absorbent together with the pressing member to the container, and removing the pressing member from the container while the absorbent is held in the container, wherein the pressing member contacting with the absorbent is diselectrified.
The absorbent to be inserted to the container by the method, may be made of a material selected from the group consisting of polyurethane, polypropylene, and polyethylene.
The container receiving the absorbent by the method, may be made of one of polypropylene, a polystyrene-based resin, and polyethylene terephthalate.
The pressing members for compressing the absorbent in the method, may be either coated with polytetrafluoroethylene (hereinafter referred to as PTFE), or covered with PTFE sheet thereon.
The pressing members for compressing the absorbent in the method, may be covered with polyethylene film thereon.
Further, the pressing members for compressing the absorbent in the method, may be coated with a fluorocarbon resin.
The pressing members for compressing the absorbent in the method may be made of a PTFE resin.
According to another aspect of the present invention, a container receiving an absorbent is produced by a method for inserting an absorbent to the container of which receiving space is smaller than the absorbent, the method comprising the steps of compressing the absorbent with a pressing member, inserting the absorbent together with the pressing member, and removing the pressing member from the container while the absorbent is held in the container, wherein the pressing member contacting with the absorber is capable of being diselectrified. The container may be made of one of polypropylene, a polystyrene-based resin, and polyethylene terephthalate, and the absorbent may be made of one of polyurethane, polypropylene, and polyethylene.
According to still another aspect of the present invention, a method for inserting an absorbent to a container comprises: a first step of compressing the absorbent with a pair of pressing members opposed to each other, a portion of the absorbent unevenly protruding from the pressing members; a second step of compressing the absorbent with a pair of pressing members opposed to each other, in a direction crossing the direction of the compression in the first step; a step of inserting the absorbent to the container together with the pressing members maintaining the absorbent in a compressed state; and a step of removing the pressing members from the container while the absorbent is held in the container.
By this method, the density of the absorbent is distributed therein varying depending on the portion thereof, which is produced by preventing compressive force from being evenly transmitted in the absorbent, by the effect of the frictional force acting between the absorbent and the pressing members, generated by compressing the absorbent under compression by a pair of pressing members, with another pair of other pressing members in the compression direction crossing the compression direction by the former pressing members. The absorbent is prevented from wrinkling, by inserting the pressing members together with the absorbent, clamping the absorbent in a compressed state.
In the method, the protruding length of the absorbent, from the edges of the pressing members, may be 0.01 to 0.5 times as large as the length, in the protruding direction, of the absorbent, which enables the density distribution in the absorbent to be varied as desired.
In the method, the density distribution in the absorbent may be produced along the direction of compression in the second step, by compressing, with the pressing members in the second step, the protruding portion of the absorbent compressed by the pressing members in the first step.
Further, in the method, the container may be provided with a liquid outlet adjacent to a position in the container, where a relatively large volume of the absorbent protrusion from the edges of the pressing members used in the first step is received.
According to a further aspect of the present invention, a container receiving an absorbent is provided, made by a method comprising: a first step of compressing the absorbent with a pair of pressing members opposed to each other, a portion of the absorbent unevenly protruding from the pressing members; a second step of compressing the absorbent with another pair of pressing members opposed to each other, in a direction crossing the direction of the compression in the first step; a step of inserting the absorbent to the container together with the pressing members maintaining the absorbent in a compressed state; and a step of removing the pressing members from the container while the absorbent is held in the container.
The container made by the method may utilize the liquid added to the absorbent more efficiently than a liquid container having an evenly compressed absorbent, because the absorbent is compressed so that the density thereof is distributed therein varying depending on the portion of the absorbent.
In the method for manufacturing the container whereby the container is provided as described above, the protruding length of the absorbent, from the edges of the pressing members, may be 0.01 to 0.5 times as large as the length, in the direction of protrusion, of the absorbent, which enables the density distribution in the absorbent to be varied as desired.
In the method wherein the container is provided as described above, the portion of the absorbent, protruding from the edges of the pressing members, may be compressed by the pressing members in the second step.
The container made by the method as described above may be provided with a liquid outlet adjacent to a position in the container, where a relatively large volume of the absorbent protrusion from the edges of the pressing members used in the first step is received.
According to a still further aspect of the present invention, a method for inserting an absorbent to a container comprises: a first step of compressing the absorbent with a pair of pressing members opposed to each other, provided with diselectrifying means, a portion of the absorbent unevenly protruding from the pressing members: a second step of compressing the absorbent with another pair of pressing members opposed to each other, provided with diselectrifying means, in a direction crossing the direction of the compression in the first step; a step of inserting the absorbent to the container together with the pressing members maintaining the absorbent in a compressed state; and a step of removing the pressing members from the container while the absorbent is held in the container.
According to a yet further aspect of the present invention, a container receiving an absorbent is provided, made by a method which comprises: a first step of compressing the absorbent with a pair of pressing members opposed to each other, provided with diselectrifying means, a portion of the absorbent unevenly protruding from the pressing members; a second step of compressing the absorbent with another pair of pressing members opposed to each other, provided with diselectrifying means, in a direction crossing the direction of the compression in the first step; a step of inserting the absorbent to the container together with the pressing members maintaining the absorbent in a compressed state; and a step of removing the pressing members from the container while the absorbent is held in the container.
Further objects, features, and advantages of the present invention will become apparent from the following description of the preferred embodiments with reference to the attached drawings.